Adenine Phosphoribosyltransferase in Plant Tissues: Some Effects of Kinetin on Enzymic Activity
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چکیده
منابع مشابه
Adenine phosphoribosyltransferase in plant tissues: some effects of kinetin on enzymic activity.
Adenine phosphoribosyltransferase activity was measured in extracts of soybean (Glycine max var. Acme) callus and of senescing barley leaves (Hordeum distichon c.v. Prior). The enzyme from soybean callus had Michaelis constants for adenine and 5-phosphoribosyl pyrophosphate of 1.5 and 7.5 mum respectively and was inhibited by AMP and stimulated by ATP. The presence of kinetin was found to consi...
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The mechanism of reaction of adenine phosphoribosyltransferase from Ehrlich ascites tumor cells was investigated kinetically by initial velocity and product inhibition studies. The data are consistent with a mechanism in which 5-phosphoribosylpyrophosphate reacts with the enzyme to form an intermediate, presumably an enzyme-ribose 5-phosphate complex, with which adenine then reacts to form aden...
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ژورنال
عنوان ژورنال: Plant Physiology
سال: 1968
ISSN: 0032-0889,1532-2548
DOI: 10.1104/pp.43.4.645